Dumbbell

ABSTRACT

The present invention relates to a dumbbell and especially relates to an improvement on an assembly mode of a grip rod and flanges at both ends thereof in the dumbbell. The present invention axially positions the grip rod and the flange by the assembly of the first assembly groove in an L shape on the grip rod and the positioning block on the flange, then circumferentially positions the grip rod and the flange by plugging a positioning pin in the first assembly groove of the grip rod and the second assembly groove of the flange simultaneously, in cooperation with the shaft-hole fitting of the grip rod and the flange themselves, thereby implementing screw-free installation of the grip rod and the flange, simple manufacturing, a low cost and a high installation efficiency.

RELATED APPLICATIONS

This application claims priority to Chinese Patent Application 202023084311.0, filed on Dec. 18, 2020, which is incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a field of the fitness equipment, specifically relates to a dumbbell, and especially relates to an improvement on an assembly mode of a grip rod and flanges at both ends thereof in the dumbbell.

BACKGROUND

As the common fitness equipment, dumbbells are favored by all kinds of fitness enthusiasts. A current adjustable dumbbell includes a grip rod of which both ends are fixedly assembled with flanges. In the prior art, the grip rod and the flanges at both ends thereof are generally fixed together by screw connection. The manufacturing process is more complicated, and the installation is more inconvenient as well.

SUMMARY

Therefore, in view of the above problems, the present invention provides a dumbbell with an optimized structure.

The present invention is realized by employing a following technical solution:

the present invention provides a dumbbell, including a grip rod and flanges assembled at both ends of the grip rod, and further including a positioning pin, wherein an end portion of the grip rod is provided with a first assembly groove, which includes a first vertical groove that is arranged in an axial direction of the grip rod from an end face of the grip rod and a first horizontal groove that is arranged in an circumferential direction of the grip rod, the first vertical groove and the first horizontal groove are communicated and joined, so that the first assembly groove is in an L shape, a flange has a center hole, which has a first hole end and a second hole end, a diameter of the center hole matches an outer diameter of the end portion of the grip rod, the end portion of the grip rod is inserted into the center hole from the first hole end, an inner wall of the center hole is provided with a second assembly groove, which includes a second vertical groove that is arranged in an axial direction of the center hole from the second hole end, the inner wall of the center hole is fixedly provided with a positioning block adjacent to the second vertical groove, a shape of the positioning block matches the first assembly groove, the positioning block is aligned and inserted into the first vertical groove, and follows along the first vertical groove to abut against a groove bottom of the first vertical groove, and the grip rod and the flange are relatively rotated to make the positioning block snap into the first horizontal groove, the positioning pin is inserted into the first vertical groove and the second vertical groove simultaneously to restrict relative rotation of the grip rod and the flange, thereby implementing the axial and circumferential positioning of the grip rod and the flange.

Wherein, in order to facilitate a design and manufacturing of the positioning pin, it is preferable that the groove widths of the first vertical groove and the second vertical groove are approximately equal, and the positioning block and the second vertical groove are combined to form an L-shaped structure approximately matching the first assembly groove, so that when the positioning block is snapped into the first horizontal groove, the first vertical groove and the second vertical groove are able to substantially overlap.

Wherein, in order to enhance stability and reliability of the positioning pin that is plugged in the first assembly groove and the second assembly groove, it is preferable that the second assembly groove further includes a second horizontal groove that is arranged in the second hole end in an circumferential direction of the center hole, the second horizontal groove is communicated with the second vertical groove, so that the second assembly groove is in an inverted L shape, the positioning pin is in an inverted L shape and includes an axial extension matching the first vertical groove and the second vertical groove and a circumferential extension matching the second horizontal groove.

Wherein, in order to prevent the positioning pin from falling inwardly from a radial direction of the center hole during assembly process, which affects an assembly efficiency, it is preferable that a groove wall of at least one side of the second vertical groove is in a concave U-shaped structure, and a side edge of the positioning pin corresponding to the groove wall is in a convex U-shaped structure.

Wherein, in order to enhance the assembly efficiency, it is preferable that the second hole end is provided with a reduced diameter step for limiting the end portion of the grip rod.

Wherein, in order to facilitate a design and manufacturing of the positioning pin, it is preferable that an end portion of the positioning block facing away from the second hole end is flush with a groove bottom of the second vertical groove.

Wherein, in order to enhance reliability of the assembly and fixation of the grip rod and the flange, it is preferable that there are two first assembly grooves that are 180° symmetrically disposed at each end portion of the grip rod, and there are also two second assembly grooves that are 180° symmetrically disposed corresponding to the first assembly groove.

Wherein, in order to enhance reliability of the assembly and fixation of the grip rod and the flange, and in consideration of the installation and manufacturing, it is preferable that the first assembly groove and the second assembly groove are rectangular grooves, and the positioning block is rectangular.

Wherein, in order to implement pre-positioning of the assembly of the grip rod and the flange, and to ensure coaxiality of the two to a certain extent, it is preferable that the grip rod is a tubular structure having an inner hole, and includes an inner tube and an outer tube sleeved and fixed on an outer periphery of the inner tube, both ends of the inner tube are exposed out of the outer tube, the first assembly grooves are disposed at both ends of the inner tube, both ends of the outer tube are further provided with inserting portions protruding in its axial direction, the flange has slots matching the inserting portions, and the inserting portions are in an inserted-sleeved connection with the slots when the grip rod is inserted into the center hole.

The present invention has the following advantageous effects: the present invention axially positions the grip rod and the flange by the assembly of the first assembly groove in an L shape on the grip rod and the positioning block on the flange, then circumferentially positions the grip rod and the flange by plugging a positioning pin in the first assembly groove of the grip rod and the second assembly groove of the flange simultaneously, in cooperation with the shaft-hole fitting of the grip rod and the flange themselves, thereby implementing screw-free installation of the grip rod and the flange, simple manufacturing, a low cost and a high installation efficiency.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic view of an adjustable dumbbell in an embodiment;

FIG. 2 is a schematic view of a dumbbell piece in the embodiment;

FIG. 3 is a schematic view of a dumbbell body in the embodiment;

FIG. 4 is a cross-sectional view of the dumbbell body in the embodiment;

FIG. 5 is an exploded view of a structure of the dumbbell body in the embodiment;

FIG. 6 is a schematic view of a grip rod in the embodiment;

FIG. 7 is a schematic view of a flange in the embodiment (first angle);

FIG. 8 is a schematic view of the flange in the embodiment (second angle);

FIG. 9 is a schematic view of an assembly of the flange and the grip rod by a positioning pin in the embodiment;

FIG. 10 is a schematic view of another feasible assembly of the flange and the grip rod by the positioning pin in the embodiment;

FIG. 11 is a schematic view of a planetary gear system in the embodiment;

FIG. 12 is an exploded view of a structure of the planetary gear system in the embodiment; and

FIG. 13 is a sectional schematic view of a gear shaft in the embodiment.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The present invention provides accompanying drawings in order to further illustrate respective embodiments. These drawings are a part of the contents disclosed by the present invention, which are mainly used to illustrate the embodiments and can explain an operation principle of the embodiments in cooperation with the relevant depiction in the description. With reference to these contents, other possible embodiments and the advantages of the present invention should understood by those ordinarily skilled in the art. The components in the drawings are not drawn in proportion, and similar component symbols are generally used to represent similar components.

Now the present invention is further described in conjunction with the drawings and the specific embodiments.

Referring to FIGS. 1-2, as a preferable embodiment of the present invention, it provides an adjustable dumbbell, including the dumbbell body 10 approximately in an “I” shape and several dumbbell pieces installed and disposed at both ends of the dumbbell body 10, first dumbbell pieces at both ends of the dumbbell body 10 are fixedly connected with the dumbbell body 10, and remaining dumbbell pieces are cumulatively installed on the first dumbbell pieces at both ends of the dumbbell body 10. As shown in FIG. 2, dovetail tenons and dovetail grooves are 180° symmetrically disposed on left and right end faces of each dumbbell piece, and accumulation of the dumbbell pieces can be implemented by clamping of the dovetail tenons and the dovetail grooves on the adjacent pieces.

Referring to FIGS. 3-5, the dumbbell body 10 includes a grip rod 1, a flanges 2 fixedly disposed at both ends of the grip rod 1, a planetary gear systems 4 in driving connection with the flanges 2 and a telescopic rod assembly 6 extending inside the dumbbell body 10, the telescopic rod assembly 6 includes a first telescopic rod 61 and a second telescopic rod 62 that are approximately in a semicircular shaft shape, by rotating the grip rod 1 and via the driving of the flange 2 and the planetary gear system 4, the dumbbell body 10 finally enables the first telescopic rod 61 and the second telescopic rod 62 to extend or retract synchronously and in opposite directions, the first telescopic rod 61 and the second telescopic rod 62 pass through a center hole of the dumbbell piece to hang the dumbbell piece, thereby adjusting the number of the dumbbell pieces at both ends of the dumbbell body 10. The specific structure and the implementation method are described in details below.

Referring to FIGS. 4 and 6-8, the grip rod 1 is in a tubular shape, and includes an inner tube 11 and an outer tube 12 sleeved and fixed on an outer surface of the inner tube 11, the inner tube 11 and the outer tube 12 can be fixed as one piece by a means of welding, adhering or integral molding, the outer surface of the outer tube 12 has concave-convex texture to increase a friction of the user's grip, both ends of the inner tube 11 are exposed out of the outer tube 12, both ends of the inner tube 11 are provided with first assembly grooves 114 in an L shape, the first assembly groove 114 includes the first vertical groove 112 that is arranged in an axial direction of the inner tube 11 from an end face of the inner tube 11 and the first horizontal groove 113 that is arranged in an circumferential direction of the inner tube 11, the first vertical groove 112 and the first horizontal groove 113 are communicated and joined, so that make the first assembly groove 114 to be in an L shape, and two first assembly grooves 114 are 180° symmetrically disposed at each end of the inner tube 11 to enhance stability and reliability of the fixed assembly of the grip rod 1 and the flange 2. Both ends of the outer tube 12 are further provided with the inserting portions 121 that protrudes outwardly in its axial direction, when the grip rod 1 and the flange 2 are assembled, the inner tube 11 of the grip rod 1 is inserted into the center hole 201 of the flange 2, and the inserting portion 121 is in an inserted-sleeved connection with the slot 211 at an end portion of the flange 2 simultaneously, thereby implementing pre-positioning of the assembly of the grip rod 1 and the flange 2, and ensuring coaxiality of the two to a certain extent. An inner hole of the inner tube 11 is a stepped hole which has a limiting step 111, the limiting step 111 is used to position a gear shaft 46 that is inserted into the inner hole.

The flange 2 is approximately in a funnel shape having the center hole 201, an inner diameter of the center hole 201 is approximately equal to an outer diameter of the inner tube 11, the center hole 201 has a first hole end 25 and a second hole end 26, the grip rod 1 is inserted into the center hole 201 from the first hole end 25, and the second hole end 26 is provided with a reduced diameter step 24 to form a stop and limit to the inner tube 11. An inner wall of the center hole 201 is provided with a second assembly groove 29 in an inverted L shape, which is formed by communicating a second vertical groove 291 that is arranged in an axial direction of the center hole 201 from the second hole end 26 and a second horizontal groove 292 that is arranged in the second hole end 26 in an circumferential direction of along the center hole 201, an inner wall of the center hole 201 is fixedly provided with a rectangular positioning block 28 adjacent to the second vertical groove 291, widths of the second vertical groove 291 and the first vertical groove 112 are approximately the same, the positioning block 28 and the second vertical groove 291 are combined to form an L-shaped form substantially matching the first assembly groove 114, so that the first vertical groove 112 and the second vertical groove 291 are able to overlap when the positioning block 28 is snapped into the first horizontal groove 113, thereby facilitating a shape design and manufacturing of the positioning pin 7. A shape of the positioning block 28 matches the first assembly groove 114, and an end face of the positioning block 28 facing away from the second hole end 26 is flush with a groove bottom of the second vertical groove 291, so that while assembled, a groove bottom of the first vertical groove 112 is flush with the groove bottom of the second vertical groove 291 to facilitate the shape design and the manufacturing of the positioning pin 7. As shown in FIG. 9, when the flange 2 and the grip rod 1 are assembled:

1. the positioning block 28 is aligned with the first vertical groove 112 of the first assembly groove 114, the inner tube 11 is inserted into the center hole 201 along an extending direction of the first vertical groove 112 until the positioning block 28 abuts against the groove bottom of the first vertical groove 112, and an outer end face of the inner tube 11 is also stopped by the reduced diameter step 24 at the same time;

2. the grip rod 1 is rotated to make the positioning block 28 snap into the first horizontal groove 113, so that the grip rod 1 and the flange 2 complete axial positioning, and after the grip rod 1 is rotated, the vertical groove 112 is also aligned with the second vertical groove 291 in the circumferential direction so as to overlap together;

3. the positioning pin 7 is used to be inserted into the first vertical groove 112 and the second vertical groove 291 at the same time to restrict relative rotation of the grip rod 1 and the flange 2, so that the grip rod 1 and the flange 2 complete circumferential positioning.

The positioning pin 7 is substantially in an L shape, and includes an axial extension 71 matching the shapes of the first vertical groove 112 and the second vertical groove 291 and a circumferential extension 72 matching the shape of the second horizontal groove 292. As shown in FIG. 10, in other embodiments, the second assembly groove 29 may also only have the second vertical groove 291, and the positioning pin 7 may also be set as a vertical form matching the second vertical groove 291 as shown in the figure, which can also restrict the relative rotation of the grip rod 1 and the flange 2. However, in this embodiment, the circumferential extension 72 is provided to be assembled with the second horizontal groove 292 to further enhance the stability and reliability of the positioning pin 7 plugged into the first assembly groove 114 and the second assembly groove 29. In order to prevent the positioning pin 7 from falling inwardly from a radial direction of the center hole 201 during an assembly process, which affects the assembly efficiency, the groove wall 293 of a side of the second vertical groove 291 is in a concave U-shaped structure, and correspondingly, one side edge 73 of the positioning pin 7 is in a convex U-shaped structure, so that when the positioning pin 7 is plugged into the second vertical groove 291, the positioning pin 7 is restricted from falling into the center hole 201 through the cooperation of the groove wall 293 and the side edge 73. In other embodiments, groove walls of both sides of the second vertical groove 291 may be set as the U-shaped structures, and the corresponding both side edges of the positioning pin 7 are in the convex U-shaped structure.

The positioning block 28 is rectangular. In other embodiments, it may also be circular and other shapes. However, it is disposed to be rectangular to cooperate with the rectangular first assembly groove 114 and second assembly groove 29, which can further improve the reliability of assembly.

In this embodiment, the grip rod and the flange are axially positioned through the L-shaped first assembly groove on the grip rod and the positioning block on the flange, then are circumferentially positioned by plugging a positioning pin in the first assembly groove of the grip rod and the second assembly groove of the flange simultaneously, in cooperation with the shaft-hole fitting of the grip rod and the flange themselves, thereby implementing screw-free installation of the grip rod and the flange, simple manufacturing, a low cost and a high installation efficiency.

The flange 2 further includes a housing portion 21, which is in a reduced cone shape and includes a small-diameter end toward the grip rod 1 and a large-diameter end toward the planetary gear system 4, the small-diameter end is provided with a slot 211 for the inserted-sleeved connection with the inserting portion 121 of the outer tube 12, and the outer diameter of the large-diameter end is approximately equal to that of an outer casing 41 of the planetary gear system 4, so that the large-diameter end is butted with the outer casing 41 of the planetary gear system 4 to substantially close the planetary gear and prevent the entering of dust and other problems.

Referring to FIGS. 10-13, the planetary gear system 4 may include the outer casing 41, an inner ring gear 42 disposed at an inner side of the outer casing 41, a load-bearing iron ring 43, a planetary wheel 44, a planetary carrier 45 and a gear set 46 as a sun wheel. The gear shaft 46 includes an shaft and a first gear 461 as an integral, the gear shaft 46 includes a hollowed shaft hole, an inner wall of the shaft hole is provided with a concave helical groove 462, which is used to engage with an external thread on the first telescopic rod 61 or the second telescopic rod 62 to drive the first telescopic rod 61 or the second telescopic rod 62 to extend or retract when the gear shaft 46 is rotated. The planetary carrier 45 is a revolving body with a substantially T-shaped cross-section, the planetary wheel 44 is rotatably sleeved on the planetary carrier 45, the outer casing 41 is formed with a planetary carrier mounting hole 414 where the planetary carrier 45 is inserted and fixed, so that the planetary wheel 44 is mounted on the outer casing 41 by the planetary carrier 45. In this embodiment, five planetary wheels 44 are provided in a circle arrangement. In other embodiments, other proper number of the planetary wheels can be selected according to the load born by the planetary wheel. The inner ring gear 42 is constantly engaged with the planetary wheel 44, the outer casing 41 has the center hole 412 for cooperating with the gear shaft 46, one end of the gear shaft 46 is inserted into the center hole 412, the first gear 461 on the gear shaft 46 is engaged with the planetary wheel 44, so that the inner ring gear 42, the planetary wheel 44, the planetary carrier 45 and the first gear 461 form a planetary gear mechanism, the first gear 461 serves as the sun wheel, and when the inner ring gear 42 is rotated actively, the first gear 461 is rotated passively, and the planetary gear forms a speed-up transmission relationship.

The load-bearing iron ring 43 is assembled and fixed with the inner ring gear 42, wherein an end face of the inner ring gear 42 is provided with a boss 421 protruding in its axial direction, and the load-bearing iron ring 43 is provided with an insertion hole 431 corresponding to the boss 421, so that the boss 421 is inserted into the insertion hole 431 to implement the cooperation of the load-bearing iron ring 43 and the inner ring gear 42. The load-bearing iron ring 43 is further fixedly assembled with the flange 2, wherein the inner ring gear 42 and the load-bearing iron ring 43 are respectively provided with a first slot 423 and a second slot 433 at corresponding positions for a first pin 23 to be inserted and cooperated, the load-bearing iron ring 43 is provided with a through hole 432 whose position corresponds to a screw hole 27 of the flange 2, when the flange 2 is engaged with the planetary gear system 4, the first pin 23 is aligned and inserted into the first slot 423 (the second slot 433) to complete the positioning, and then a screw is passed through the through hole 430 to be fixedly locked in the screw hole 27, so that the load-bearing iron ring 43, the inner ring gear 42 and the flange 2 are connected as one piece. In order to facilitate the installation and locking of the screw, an outer ring of the inner ring gear 42 is further provided with a groove 422 for giving way to the screw, and the outer casing 41 is formed with a screw insertion hole 415. By the assembly relationship that the load-bearing iron ring 43, the inner ring gear 42 and the flange 2 are connected as one piece, the inner ring gear 42 can be rotated while rotating the flange 2, and since the flange 2 is fixedly assembled with the grip rod 1, the inner ring gear 42 can be rotated while rotating the grip rod 1, so that the gear shaft 46 is rotated through the driving of the planetary gear mechanism, then the gear shaft 46 drives the first telescopic rod 61 and the second telescopic rod to extend or retract through the engagement of the helical groove 462 inside the shaft hole and the external thread on the first telescopic rod 61 or the second telescopic rod 62.

An outer side of the outer casing 41 is screwed and fixedly connected with the dumbbell piece by a dumbbell piece mounting plate 5, so that by gravity of the dumbbell piece, the outer casing 41 is able to keep stationary when the grip rod 1 is rotated.

Although the present invention has been particularly shown and described in conjunction with preferred embodiments, those skilled in the art should understand that various changes in form and detail may be made to the present invention without departing from the spirit and scope of the present invention as defined by the appended claims, which fall within the protection scope of the present invention. 

What is claimed is:
 1. A dumbbell, comprising: a grip rod, flanges assembled at both ends of the grip rod, and a positioning pin, wherein: an end portion of the grip rod is provided with a first assembly groove, the first assembly groove comprises a first vertical groove that is arranged in an axial direction of the grip rod from an end face of the grip rod and a first horizontal groove that is arranged in a circumferential direction of the grip rod, the first vertical groove and the first horizontal groove are in communication and joined so that the first assembly groove is in an L shape, each of the flanges has a center hole, the center hole has a first hole end and a second hole end, a diameter of the center hole matches an outer diameter of the end portion of the grip rod, the end portion of the grip rod is inserted into the center hole from the first hole end, an inner wall of the center hole is provided with a second assembly groove, the second assembly groove comprises a second vertical groove that is arranged in an axial direction of the center hole from the second hole end, the inner wall of the center hole is fixedly provided with a positioning block adjacent to the second vertical groove, a shape of the positioning block matches the first assembly groove, the positioning block is aligned and inserted into the first vertical groove and follows along the first vertical groove to abut a groove bottom of the first vertical groove, the grip rod and each of the flanges are relatively rotatable to make the positioning block snap into the first horizontal groove, and the positioning pin is inserted into the first vertical groove and the second vertical groove simultaneously to restrict relative rotation of the grip rod and each of the flanges, thereby implementing axial positioning and circumferential positioning of the grip rod and each of the flanges.
 2. The dumbbell of claim 1, wherein: groove widths of the first vertical groove and the second vertical groove are equal, and the positioning block and the second vertical groove are combined to form an L-shaped structure matching the first assembly groove so that when the positioning block is snapped into the first horizontal groove, the first vertical groove and the second vertical groove are configured to overlap.
 3. The dumbbell of claim 1, wherein: the second assembly groove further comprises a second horizontal groove that is arranged in the second hole end in a circumferential direction of the center hole, the second horizontal groove is in communication with the second vertical groove so that the second assembly groove is in an inverted L shape, and the positioning pin is in an inverted L shape and comprises an axial extension matching the first vertical groove and the second vertical groove and a circumferential extension matching the second horizontal groove.
 4. The dumbbell of claim 1, wherein: a groove wall of at least one side of the second vertical groove defines a concave U-shaped structure, and a side edge corresponding to a groove wall of the positioning pin defines a convex U-shaped structure.
 5. The dumbbell of claim 1, wherein the second hole end is provided with a reduced diameter step for limiting the end portion of the grip rod.
 6. The dumbbell of claim 1, wherein an end portion of the positioning block facing away from the second hole end is flush with a groove bottom of the second vertical groove.
 7. The dumbbell of claim 1, wherein: there are two of the first assembly grooves that are 180° symmetrically disposed at each end portion of the grip rod, and there are two of the second assembly grooves that are 180° symmetrically disposed corresponding to the first assembly grooves.
 8. The dumbbell of claim 1, wherein: the first assembly groove and the second assembly groove are rectangular grooves, and the positioning block is rectangular.
 9. The dumbbell of claim 1, wherein: the grip rod is a tubular structure having an inner hole, the tubular structure comprises an inner tube and an outer tube sleeved and fixed on an outer periphery of the inner tube, both ends of the inner tube are exposed out of the outer tube, the first assembly grooves are disposed at both ends of the inner tube, both ends of the outer tube are provided with inserting portions convexly protruding along an axial direction of the outer tube, each of the flanges has slots matching the inserting portions, and the inserting portions are in an inserted-sleeved connection with the slots when the grip rod is inserted into the center hole. 